Ecology: r-selected and K-selected Species

r-selected Species

• Characterized by high rates of population growth.
• Feature short life spans and numerous small offspring with minimal to no parental care.
• Many offspring die young due to lack of nurturing.
• Sustain species by producing a large number of offspring.
• Notable examples include algae, bacteria, frogs, most insects, and many fish.
• Tend to be opportunistic, reproducing when conditions are favorable.
• Exhibit irregular population patterns.
• Generally classified as generalists, adapting to various environments.
• Invasive species, often r-selected, thrive due to high reproductive potential and quick maturation, easily colonizing new areas and competing with native species.

K-selected Species

• Typically reproduce later in life with fewer offspring, resulting in longer life spans.
• Offspring develop safely inside mothers and are born large.
• After birth, offspring mature slowly, receiving care and protection from one or both parents.
• Often found near carrying capacity, balancing population with resource availability.
• Examples include most mammals, elephants, whales, birds of prey, and long-lived plants.
• Experience high competition for resources within their habitats, reflecting their specialized nature.
• Classified as specialists, adapted to specific niches.

Comparison of r and K-selected Species

• r-selected species thrive in disturbed environments, whereas K-selected species do not.
• Competition for resources is relatively low for r-selected species but high for K-selected species.
• K-selected species are more adversely affected by invasives due to being specialists with low population growth rates, while r-selected species can switch resources, minimizing competition impacts.
• Classifying species should be viewed as a spectrum rather than strict categories.

Biotic Potential

• Refers to the maximum reproduction rate of a population under ideal conditions, influencing species' survival and adaptability.

This quiz explores the characteristics of r-selected and K-selected species, highlighting their reproductive strategies, life spans, and population dynamics. Learn about the adaptations that enable r-selected species to thrive in varying environments, as well as the nurturing tendencies of K-selected species. Test your knowledge on these fundamental ecological concepts.